E-mail address tagging (jsmith+tagtext@example.com) gets lost on Postfix with Spamassassin on CentOS 8

[Roland Kronqvist]

I have a problem on my Postfix mail gateway server that is set up to
accept e-mail address tagging. The tagging itself works, I have tested it
and I receive the messages with the tag in the address. The problem is
that when I installed Spamassassin, the tagging gets lost, all mails are
delivered without the tag. My Postfix server act as a gateway for inbound
mail where spamfiltering and so on is done and then relay all mail to my
Exchange-server. I have tried to shut off Spamassassin to ensure the tag
isn't removed within that.

This is the config in master.cf for Spamassassin:

smtp inet n - n - - smtpd -o content_filter=spamassassin


I think it's here where the tagging gets lost:

spamassassin unix - n n - - pipe flags=R user=spamd argv=/usr/bin/spamc -
e /usr/sbin/sendmail -oi -f ${sender} ${recipient}

If I have got this right, the last row passes the addresses to sendmail
and the ${sender} ${recipient} defines that. But I have tried different
settings, but I'm lost. Maybe someone can help here?